Is there any way to PERMAMENTLY eliminate rear main oil leaks?

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George Jets said:
Yes I was wondering about the knurled area where the seal touches, that knurling is supposed to wind the oil back into the engine as the crank is turning.
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Gus Wilson had words to say on that subject.

For awhile there was a special anti-leak rear main bearing offered for the Slant-6. Had two diagonal grooves cut into the bearing surface. As far as I know it's been unavailable for a long time, but—again—it should be possible to get a reasonably dry rear main seal with careful attention to parts selection and install technique, and without any special rear main bearing.
 
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1WildRT said:
There's an easy way to stop the rear main from leaking permanently....

Drain the oil.... No oil = no leak...
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Great minds think alike. I was going to post that but thought for sure someone else would chime in.
 
slantsixdan said:
Gus Wilson had words to say on that subject.

For awhile there was a special anti-leak rear main bearing offered for the Slant-6. Had two diagonal grooves cut into the bearing surface. As far as I know it's been unavailable for a long time, but—again—it should be possible to get a reasonably dry rear main seal with careful attention to parts selection and install technique.
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That Gus guy really gets around. lol
 
slantsixdan said:
Gus Wilson had words to say on that subject.

For awhile there was a special anti-leak rear main bearing offered for the Slant-6. Had two diagonal grooves cut into the bearing surface. As far as I know it's been unavailable for a long time, but—again—it should be possible to get a reasonably dry rear main seal with careful attention to parts selection and install technique, and without any special rear main bearing.
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Reading that actually jiggled a few brain cells . That was actually a real occurrence, but I don't think it was Mopar. But, anyway, I didn't think of this because of it being a new engine.
Is the PCV system connected and working properly. That used to be a common problem with slants.
 
Nick's Garage had a video on Old Leaky, a 383 that he could not stop from leaking at the real main. After numerous attempts, they found that the engine was line-honed and the cap side seal was barely touching. Fix? Grind a little off the mating face of the cap bringing the seal tighter to the crank. Problem solved.
 
My rear main on a 76 Slant leak immediately after rebuild. The rebuild was performed by an experience builder although he did not stagger the seal with the gland. I installed the one piece seal from fastfish in the manner that Slantsixdan stated. Over 500 miles later still no leak.
 
Heyseed said:
My rear main on a 76 Slant leak immediately after rebuild. The rebuild was performed by an experience builder although he did not stagger the seal with the gland. I installed the one piece seal from fastfish in the manner that Slantsixdan stated. Over 500 miles later still no leak.
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I hope the result continues but unfortunately 500 miles doesn't mean much.. Having worked in the trade for many years I've seen to many seals that work fine for a thousand miles then start puking oil...

Best thing for rear main seals was when manufacturers quit putting a big flange on the back of the crank and started using a full circle one piece seal...
 
LO23M8B said:
Want a leak free car, buy electric.:)
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Tesla cars have a complicated coolant system with many leaks reported. Worst is a seal to the rotating armature of the large drive unit, which typically leak internally within 100K miles and can ruin the motor and inverter if not caught early. Tesla dropped liquid cooling of the armature and now an aftermarket fix-it kit blanks it off. Can leak coolant inside the HV battery, which is costly. They also can leak gearbox oil.
 
Might also be leaking from the oil pan gasket. The two pan bolts there screw into the aluminum rear-seal holder and often get stripped. The shop should have verified those threads while the part was off and used a Helicoil repair if damaged. I bought the $35 silicone pan and valve cover gasket for the slant from Real Gaskets of TN. Don't overtorque them. I degreased all the bolt holes and used red thread-lock since the bolts are torqued so low, they might back-out otherwise. Best is a silicone gasket captured in a groove, like an O-ring so you bolt up tight w/ metal-metal contact, like some newish engines have. Someday, a clever Chinese company like Ningbo might make such cast-aluminum oil pans for classic engines.
 
RLF Cuda said:
Nick's Garage had a video on Old Leaky, a 383 that he could not stop from leaking at the real main. After numerous attempts, they found that the engine was line-honed and the cap side seal was barely touching. Fix? Grind a little off the mating face of the cap bringing the seal tighter to the crank. Problem solved.
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Wouldn't that change the bearing fit and centerline of hole in relation to the crank. Shim the seal?
 
rubbery ones slowly squish out sideways one way or the other, eventually split and push out at the bolts, keeping that thing on the rail becomes hard work you don't need...

Glue a cork one to the cover, smear the oil off the edge of the head and do up the bolts to spec. job done, anything else is a waste of $$$

dave
 
Dave999 said:
rubbery ones squish, eventually split and push out at the bolts, keeping that thing on the rail becomes hard work you don't need...

Glue a cork one to the cover, smear the oil off the edge of the head and do up the bolts to spec. job done, anything else is a waste of $$$

dave
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Realgaskets material is use on aircraft so are high quality... unlike others out there.
 
Ricks70Duster340 said:
Realgaskets is the bomb. I use their gaskets for not only my big block oil pan (with the windage tray) and the 727 pan. No leaks from them at all! Great folks to work with too.
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I'm a big fan of their silicone garden hose (=washing machine hose) washers. That's an appropriate application for that red-orange silicone material they use. And yeah, they're great to work with. But I've seen too much incompatibility of their apparently one-and-only material with too many applications to get onside with their idea that it's suitable for whatever one is trying to seal up.
 
Ricks70Duster340 said:
Realgaskets material is use on aircraft so are high quality... unlike others out there.
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1. {{citation needed}} on RG's gaskets being made out of a material used for airplanes. Because y'see, sometimes even really nice people tell fibs about products they sell. And sometimes people who don't even sell the product parrot those fibs, because everyone likes to feel good about the purchase decisions they've made.

2. Even if it's true…what do you think that proves? Airplanes have a lot of gaskets to seal a lot of things to a lot of other things in the presence of a lot of different materials. So do cars. Lotta different gasket materials in cars and in airplanes; there's no one single be-all/do-all gasket material.

3. Airplane gaskets aren't necessarily high quality (ask your local aviation mechanic; they have problems with crummy parts, just like we do).

4. A material that works great in one application—even if that application is in an airplane!—doesn't necessarily work great (or even work well) in another application.

None of this is hard to understand, except maybe if one doesn't wanna.
 
slantsixdan said:
1. {{citation needed}} on RG's gaskets being made out of a material used for airplanes. Because y'see, sometimes even really nice people tell fibs about products they sell. And sometimes people who don't even sell the product parrot those fibs, because everyone likes to feel good about the purchase decisions they've made.

2. Even if it's true…what do you think that proves? Airplanes have a lot of gaskets to seal a lot of things to a lot of other things in the presence of a lot of different materials. So do cars. Lotta different gasket materials in cars and in airplanes; there's no one single be-all/do-all gasket material.

3. Airplane gaskets aren't necessarily high quality (ask your local aviation mechanic; they have problems with crummy parts, just like we do).

4. A material that works great in one application—even if that application is in an airplane!—doesn't necessarily work great (or even work well) in another application.

None of this is hard to understand, except maybe if one doesn't wanna.
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My point is this: the gaskets do their job and seal what I've put them on. You are welcome to question anything you want, but they worked for me, and I stand behind them.
 
I've used the "Real Gaskets" first hand, so I have DIRECT experience. I was optimistic, given all their marketing talk. Plus, they are very cost effective, so it didn't seem like they were after my money, anyway. All I can say is, they suck. No matter what torque spec I tried, theirs, or a variety of torque specs after I tried theirs, nothing stopped their valve cover gasket from leaking. Nothing. And yes, I made sure the valve cover rail was STRAIGHT and the bolt holes were knocked back out straight. I closely inspected the valve cover rail on the head for cracks and imperfections and it was very smooth......as most of them are. All I can say is, their valve cover gasket leaked like a ***** on payday. I replaced it with a "good old" cork gasket and no more leaks. None. Zero. Zilch. So I cannot and will not recommend Real Gaskets.

That said, I tell you what I am thinking about, regarding my oil pan. I think I am going to reseal it with grey RTV only. The mating surfaces are all flat and I believe that will work. I'm going to look it over and see if I think it will work, but I believe it might.
 
Ricks70Duster340 said:
My point is this: the gaskets do their job and seal what I've put them on. You are welcome to question anything you want, but they worked for me, and I stand behind them.
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I'm glad they worked for somebody, but no matter what I tried, they sure didn't work for me.
 
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